From Illinois, the oil could go to markets and refineries across the Midwest, East Coast and Gulf Coast.

Who approved it?

The US Energy Information Administration shows the network of existing crude oil pipelines across the country.

The US Army Corps of Engineers approved the project and granted final permits in July.

By the numbers

1,172 miles: Length of Dakota Access Pipeline

30 inches: Width of the pipeline

470,000: Barrels of crude oil to be moved daily

374.3 million: Equivalent gallons of gasoline per day

Sources: Energy Access Partners, US Energy Information Administration

But the Standing Rock Sioux Tribe sued the Corps, saying the pipeline "threatens the Tribe's environmental and economic well-being, and would damage and destroy sites of great historic, religious, and cultural significance to the Tribe."

What's the argument for and against?

Actress Shailene Woodley protests against the pipeline on August 24 in Washington.

Pro: The pipeline wouldn't just be an economic boon, it would also significantly decrease U.S. reliance on foreign oil, the developer Energy Transfer Partners said. The pipeline would also help free up railways to transport "crops and other commodities currently constrained by crude oil cargos."

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But Standing Rock Sioux Chairman David Archambault II said he doesn't support moving more crude oil from North Dakota. He told CNN affiliate KFYR that Americans should look for alternative and renewable sources of energy.

"The Dakota Access pipeline would fuel climate change, cause untold damage to the environment, and significantly disturb sacred lands and the way of life for Native Americans in the upper Midwest," a petition on CredoAction.com states.

Opponents also say they're worried what would happen if the pipeline, which would go under the Missouri River, ruptured and contaminated the water supply.

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But the Midwest Alliance for Infrastructure Now backed the developer's claim that pipelines are a safe way of moving crude oil.

"Already, 8 pipelines cross the Missouri River carrying hundreds of thousands of barrels of energy products every day," the group said in a statement.

What's the economic impact?

A modified highway sign reads "No Pipeline" near the site of a protest against the Dakota Access Pipeline.

Energy Transfer Partners estimates the pipeline would bring an estimated $156 million in sales and income taxes to state and local governments. The developer also says it will add 8,000 to 12,000 construction jobs.

But Archambault said his tribe will settle for nothing less than stopping the pipeline's construction.

"We're not opposed to energy independence. We're not opposed to economic development," he told CNN. "The problem we have -- and this is a long history of problems that evolved over time -- is where the federal government or corporations take advantage of indigenous lands and indigenous rights."

What's going on with the protests?

Native Americans march to a burial ground site they say was disturbed by bulldozers building the Dakota Access Pipeline.

Law enforcement officials spent six hours pushing about 200 protesters from one area back to their main encampment. Police deployed bean bag rounds and pepper spray gas, and unleashed a high-pitched siren to disperse the crowd.

In response, protesters lit debris on fire near a bridge and threw Molotov cocktails at law enforcement, North Dakota Department of Emergency Services spokeswoman Cecily Fong said.

Around 50 cars were towed away. A handful were either burned or otherwise vandalized.

What do the landowners get?

Energy Transfer Partners said it has tried to steer the pipeline away from residential areas and has tried to reach voluntary deals with property owners "at a fair price."

But Archambault, the tribal chairman, said he thinks the Native Americans are getting short-changed once again.

"What we're opposed to is paying for all the benefits that this country receives," he said. "Whenever there's a benefit, whether it's energy independence ... whether it's economic development, tribes pay the cost. And what we see now are tribes from all over sharing the same concern that we have, saying, 'It's enough now. Stop doing this to indigenous people. Stop doing this to our indigenous lands.'"